1. Field of the Invention
The present invention relates to a copier, printer, facsimile apparatus or similar image forming apparatus and more particularly to a cleaning device for an image forming apparatus.
2. Description of the Background Art
A cleaning device for cleaning a desired member has customarily been used in machines and apparatus in various fields. An image forming apparatus, for example, includes a cleaning device for cleaning the surface of an image carrier, a cleaning device for cleaning the surface of a charge roller that charges the image carrier, and a cleaning device for cleaning the surface of an image transfer belt.
Japanese Patent Laid-Open Publication No. 7-140763, for example, discloses a cleaning device using a brush roller that contacts the surface of a member to be cleaned. The brush roller is rotated by a drive source. A brush on the brush roller and the surface of the member to be cleaned each are moved at a particular linear velocity, so that the brush scrapes off impurities deposited on the member.
However, the conventional brush roller type of cleaning device needs the drive source for driving the brush roller. Moreover, this type of cleaning device needs means for limiting the amount of bite of the brush into the desired member in order to control the permanent deformation of the brush. This increases the cost of the cleaning device and makes the cleaning device sophisticated. It is to be noted that the amount of bite of the brush refers to the maximum amount of deformation of the brush roller to occur in the radial direction when the brush is pressed against the surface of the desired member. It has been customary to control the yield of the brush by confining the amount of bite in an adequate range.
On the other hand, assume that impurities deposited on the brush of the brush roller absorb moisture in a high-humidity environment and cannot be easily removed or that a great amount of toner deposits on the brush at a time. Then, the cleaning ability of the brush roller falls with the result that a body to be cleaned is contaminated and brings about defective images. Further, to meet the increasing demand for the reduction of running cost, it is necessary to extend the lives of parts and those of units.
Technologies relating to the present invention are also disclosed in, e.g., Japanese Patent Laid-Open Publication Nos. 8-22173, 10-20696, 10-282854 and 11-219048.
It is an object of the present invention to provide a cleaning device whose brush roller maintains an expected cleaning ability even when impurities deposited on its brush absorb moisture in a high-humidity environment and cannot be easily removed or when a great amount of toner deposits on the brush at a time, thereby obviating defective images ascribable to the contamination of a body to be cleaned.
It is another object of the present invention to provide a cleaning device having a brush roller constructed into a unit for thereby extending the life of the brush roller while promoting easy, rapid replacement.
It is a further object of the present invention to provide a cleaning device having an enhanced ability to scrape off impurities deposited on a brush and achieving an extended service life.
A cleaning device of the present invention includes a brush roller having a brush held in contact with the surface of a body to be cleaned. The brush contacts the surface of the body to be cleaned due to the weight of the brush roller and rotates by following the movement of the above surface. A flicker is held in contact with the brush in order to remove toner deposited on the brush. A casing forms a chamber therein for storing the toner removed by the flicker.